The 208Pb(3He,t)208Bi reaction has been studied with the RCNP ring cyclotron at E(3He) = 450 MeV using the magnetic spectrometer Grand Raiden at θ = 0°. The Gamow-Teller resonance is strongly excited at this bombarding energy. Its microscopic structure has been investigated by measuring the direct proton decay to the neutron-hole states in 207Pb. The branching ratio for proton emission of a few % is much smaller than that for the decay of the isobaric analog state. The total width of the Gamow-Teller resonance as well as its total and partial escape widths have been determined. Several recent theoretical estimates for the escape width differ from the measured values by factors of ~ 2.5.
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